Hepatitis A
什麼是Hepatitis A
Hepatitis is an inflammation of the liver caused by several viruses. There are three principal kinds of hepatitis, A, B, and C. Hepatitis A is caused by the hepatitis A virus, B by the B virus, and C by the C virus. Hepatitis A occurs worldwide as a sporadic or epidemic illness. It is ubiquitous in developing countries where adults are usually immune due to widespread exposure and mild illness acquired as young children.
您如何獲得Hepatitis A？
Hepatitis A is transmitted through contaminated food or water, including ice. It is also transmitted directly from person to person, from shellfish harvested in sewage-contaminated water, or from fruits, vegetables or other foods that are uncooked and that were contaminated during harvesting or subsequent handling.
易感性和抵抗力
Humans are generally susceptible to hepatitis virus infection. Life-long immunity follows natural infection with hepatitis A.
有哪些症狀？
Hepatitis A virus causes an inflammation of the liver manifested by the rapid onset of fever, fatigue, loss of appetite, nausea and abdominal discomfort. Within a few days, jaundice (yellow-coloured skin) appears. In children, the infection may be unapparent or very mild. The illness can be mild and last for 1-2 weeks or can be severely disabling and last several months. Prolonged or relapsing hepatitis may occur for up to 1 year in about 15 percent of the cases. Convalescence may be prolonged, but usually patients make a complete recovery. Chronic infection does not occur. Deaths due to hepatitis A virus infection occur in 0.1 to 0.3 percent of the cases.
預防措施
預防接種可預防甲型肝炎。在180°F或85°C下沸騰或烹飪食品和飲料超過1分鐘，可使病毒滅活。水的氯化使病毒滅活。旅行者可以通過認真遵循食物和水的預防措施來降低風險。
治療
There is no specific treatment for acute hepatitis other than supportive measures.
When administered within 2 weeks of last exposure, hepatitis immune globulin is 80 to 90 percent effective in preventing clinical hepatitis A. In scientific studies, the use of the hepatitis A vaccine within 14 days after exposure provided protection equivalent to that of immune globulin.
疫苗接種
通常在哪裡發生？
甲型肝炎有高、中、低水準，低收入國家有高水準;中等收入國家有中低水準;高收入國家的甲型肝炎水準非常低。撒哈拉沙漠以南的非洲、印度和巴基斯坦的大部分地區都很高。在墨西哥、中美洲和南美洲、北非和整個中東地區都可以找到中等水準。東歐國家、俄羅斯和中國都發現低水準。在加拿大、美國、西歐國家和澳大利亞，其含量非常低。
